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We present herein a fine-tuning model for the fabrication and application of Er(III)/Tm(III)-Yb(III) co-doped ZrO2 macroporous matrix, which combines porosity and highly efficient multi-color to white light upconversion photoluminescence. By control of lanthanide doping species and concentration, as well as the excitation pumping power, the emission can be tuned among red, green or blue (RGB) primary colors in a linear fashion, and trichromatically combined white light is therefore achieved. Precise mathematical matrix models are established for prediction of color chromaticity coordinates as a relation of doping composition and pumping power, which provides a general route for the development of novel upconversion materials that are particularly useful in white light displaying, multiplexed labelling and anti-counterfeiting.

Multi-mode photoluminescence, including enolemission, keto-emission, and aggregate-related emission is achieved in a Zn-II coordination polymer from excited-state intramolecular proton transfer (ESIPT) ligands. Single-phase white light emission (WLE) and tunable emitting colors can be obtained by varying the suspending/grinding solvent system or temperature, which brings a brand-new model in developing multi-stimuli-responsive WLE materials.

Phthalate pollution in soil and vegetables in plastic agricultural greenhouses has attracted wide concern. Investigating airborne phthalates in this environment can improve understanding of air-soil or air-vegetable phthalate migration. However, studies of phthalates in plastic agricultural greenhouse air are rare. To fill this gap, 25 gas-phase and 23 particle-phase samples were collected from 12 typical plastic greenhouses in Shaanxi. 16 types of phthalates were measured by a gas chromatography-mass spectrometry system (GC-MS) to analyse their pollution features and variations. Results showed that in the air of the plastic greenhouses, the median concentration of the sum of sixteen type phthalates (∑16 phthalates) was 5305 ng m−3, with 5th-95th value of 1214–9616 ng m−3. Phthalates in gas-phase samples were over 100 times higher than the levels in particle-phase samples. Air phthalate concentrations in the plastic greenhouses were higher than those in the control groups (P

Five cyclometalated Ir(III) complexes are synthesized from a sulfonate-modified bis-benzimidazole-type organic ligand (3,3′-(2,2′-(1,3-phenylene)bis(1 H –benzo [ d ]imidazole-2,1-diyl))dipropane-1-sulfonic acid, MBS) with different ancillary ligands, and can be classified into two categories. Namely, complexes 1 and 2 (MBS-Ir-ppy and MBS-Ir-Fppy), which are electroneutral, and complexes 3–5 (MBS-Ir-bpy, MBS-Ir-Mebpy, and MBS-Ir-bpyCOOEt), which are cationic and soluble in water. These Ir(III) complexes show tunable luminescence from cyan to orangish red color in solution and yellowish red to pure red color in solid state, with moderately long lifetime (56–528 ns) and high quantum yield (35–71%).

The exploration of novel porous core–shell materials is of great significance because of their prospectively improved performance and extensive applications in separation, energy conversion, and catalysis. Here, mesoporous metal–organic frameworks (MOFs) NH2‐MIL‐101(Fe) as a core generate a shell with mesoporous covalent organic frameworks (COFs) NUT‐COF‐1(NTU) by a covalent linking process, the composite NH2‐MIL‐101(Fe)@NTU keeping retentive crystallinity with hierarchical porosity well. Importantly, the NH2‐MIL‐101(Fe)@NTU composite shows significantly enhanced catalytic conversion and selectivity during styrene oxidation. It is mainly due to the hydrophilic MOF nanocrystals readily gathering the hydrophobic reactants styrene and boosting the radical mechanism path after combining the hydrophobic COFs shell. The synthetic strategy in this systematic study develops a new rational design for the synthesis of other core–shell MOF/COF‐based hybrid materials, which can expand the promising applications.

Long persistent luminescence (LPL) materials have a unique photophysical mechanism to store light radiation energy for subsequent release. However, in comparison to the common UV source, white-light (WL) and near-infrared (NIR) excited LPL is scarce. Herein we report a metal-organic supramolecular box based on a D-π-A-type ligand. Owing to the integrated one-photon absorption (OPA) and two-photon absorption (TPA) attributes of the ligand, the heavy-atom effect of the metal center, as well as π-stacking and J-aggregation states in the supramolecular assembly, LPL can be triggered by all wavebands from the UV to the NIR region. This novel designed supramolecular kit to afford LPL by both OPA and TPA pathways provides potential applications in anti-counterfeiting, camouflaging, decorating, and displaying, among others.

A Co-MOF, [Co

To compare the effects of Morinda officinalis root and its salt-processing prodduct on rats with kidney yang deficiency from the viewpoint of energetic metabolism.The rat models for the kidney yang deficiency were established through the perfusion of methimazole. The models were treated with different dosages of Morinda officinalis root without woods and its salt-processing products extracts. The activity of liver glycogen,muscle glycogen,free fatty acid( NEFA),lipoprotein lipase( LPL),hepatic lipase( HL),liver and skeletal muscle Na+,K+ATPase,Ca2 +,Mg2 +ATPase,succinodehydrogenase( SDH) were measured by colormetric methods,and the coefficient of body fat were observed by weighing method.Morinda officinalis root without woods and its saltprocessing products could improve the energetic metabolism of kidney yang deficiency of rats. The effects of salt-processing products were better than Morinda officinalis root without woods in the same dosage.The effect of invigorating the kidney and strengthening yang of Morinda officinalis were correlated with energetic metabolism. The correct processing-products of Morinda officinalis root should be chosen with the suitable measurements in clinic.

The crack closure behavior of a nickel-based single crystal (SC) superalloy was studied based on in-situ SEM fatigue tests. Specimens in two different secondary orientations were tested at 600 °C. A model considering the anisotropy of SC superalloys was developed to analyze crack closure behavior. The results show that specimens in two orientations exhibit different cracking modes. For specimen [0 0 1]/[0 1 0], roughness-induced crack closure effect is dominant in crack closure behavior and crack closure effect is constant during crack propagation process. However, for specimen [0 0 1]/[1 1 0], plasticity-induced crack closure effect is dominant in crack closure which becomes enhanced as crack grows.

A highly fluorescent HPI-based excited-state intramolecular proton transfer (ESIPT) molecule is designed and adopted as a naked-eye colorimetric sensor to distinguish methanol, ethanol and isopropanol vapors. Amplified spontaneous emission was also observed for the C1-form single crystal of the molecule attributed to its intrinsic four-level energy states.

Distinguishable d → f or f → d energy transfer processes depending on lanthanide ions are observed in isomorphous d–f heterometallic complexes containing the Ru(II) metalloligand (LRu), which lead to sensitized NIR emission (for Nd3+ and Yb3+) or enhanced red emission of LRu (for Eu3+ and Tb3+), and represent the first eye-detectable evidence of f → d energy transfer processes in Ln–Ru bimetallic complexes. Based on the systematic luminescence and decay lifetime study, cascade f → d → f energy transfer has been proposed in Ln1–Ru–Ln2 trimetallic systems for improved NIR sensitization.

Rafting and creep modeling of single crystal superalloys at high temperatures are important for the safety assessment and life prediction in practice. In this research, a new model has been developed to describe the rafting evolution and incorporated into the Cailletaud single crystal plasticity model to simulate the creep behavior. The driving force of rafting is assumed to be the relaxation of the strain energy, and it is calculated with the local stress state, a superposition of the external and misfit stress tensors. In addition, the isotropic coarsening is introduced by the cube root dependence of the microstructure periodicity on creep time based on Ostwal ripening. Then the influence of rafting on creep deformation is taken into account as the Orowan stress in the single crystal plasticity model. The capability of the proposed model is validated with creep experiments of CMSX-4 at 950 °C and 1050 °C. It is able to predict the rafting direction at complex loading conditions and evaluate the channel width during rafting. For [001] tensile creep tests, good agreement has been shown between the model predictions and experimental results at different temperatures and stress levels. The creep acceleration can be captured with this model and is attributed to the microstructure degradation caused by the precipitate coarsening.

Creep-fatigue interaction is extremely important for the life prediction of structural components subjected to high temperature conditions. The widely used life prediction methods such as time fraction rule and ductility exhaustion method are found to be insufficient in long time regimes and cannot give a clear physical explanation for the material failure. In this paper, a generalized life prediction model is proposed on the basis of the hysteresis energy and law of energy conservation. The influence of hold time on the cyclic stress–strain behavior is described based on isochronous stress–strain curves and stress relaxation during hold time is evaluated with the time hardening rule. An analytical approach is set up to calculate the hysteresis energy for the creep-fatigue tests. The generalized hysteresis energy is used as a model parameter to predict the fatigue and creep-fatigue life of 316L(N) and it is found to have a power law relationship with the number of cycles to failure. The fatigue and creep-fatigue life predicted with the new energy-based method shows a good correlation with the experimental results from different researchers.

Porous Co–P–Pd nanotube arrays (NTAs) are prepared and used for catalyzing the hydrolysis of alkaline NaBH4 solution to generate H2. Benefiting from the unique porous structure and synergistic effect, the Co–P–Pd NTAs show a maximum hydrogen generation rate of 4216 mL per min per g catalyst and good cyclic stability.

Two-dimensional (2D) metal–organic frameworks have exhibited a range of fascinating attributes, of interest to numerous fields. Here, a calcium-based metal-organic framework with a 2D layered structure has been designed. Dual emissions relating to intralayer excimers and interlayer trapped excitons are produced, showing excitation-dependent shifting tendency, characteristic of a low dimensional semiconductor nature. Furthermore, the layer stacking by weak van der Waals forces among dynamically coordinated DMF molecules enables exfoliation and morphology transformation, which can be achieved by ultrasound in different ratios of DMF/H2O solvents, or grinding under appropriate humidity conditions, leading to nano samples including ultrathin nanosheets with single or few coordination layers. The cutting down of layer numbers engenders suppression of interlayer exciton-related emission, resulting in modulation of the overall emitting color and optical memory states. This provides a rare prototypical model with switchable dual-channel emissions based on 2D-MOFs, in which the interlayer excitation channel can be reversibly tuned on/off by top-down exfoliation and morphology transformation.

Core–shell or striped heteroatomic lanthanide metal–organic framework hierarchical single crystals were obtained by liquid-phase anisotropic epitaxial growth, maintaining identical periodic organization while simultaneously exhibiting spatially segregated structure. Different types of domain and orientation-controlled multicolor photophysical models are presented, which show either visually distinguishable or visible/near infrared (NIR) emissive colors. This provides a new bottom-up strategy toward the design of hierarchical molecular systems, offering high-throughput and multiplexed luminescence color tunability and readability. The unique capability of combining spectroscopic coding with 3D (three-dimensional) microscale spatial coding is established, providing potential applications in anti-counterfeiting, color barcoding, and other types of integrated and miniaturized optoelectronic materials and devices. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

The vast majority of PRB currently in use utilize zero valent iron (ZVI) as the reactive medium. In this paper, three laboratory columns were set up and operated under conditions simulating those anticipated in the groundwater to investigate the feasibility and efficiency of the enhanced Fe0 PRB for the remediation of the PCBs contaminated groundwater. Operating under 10°C and an effective porosity of 61% to 67% and infiltration velocity of groundwater of 0.7 to 0.8m•d-1, the average iron concentration of effluent was 0.241mg•L-1, 0.129mg•L-1 and 0.201mg•L-1, respectively, and the average dechlorination efficiency reached 49.6%, 72.6% and 58.6%, respectively, the Fe0/Zn0 based columns can accomplish 94% of PCBs removal and pH value raised from 6.87 to 10.2. Comprehensive consideration suggested that Fe0/Zn0 based PRB technology is feasible for the remediation of PCBs contaminated groundwater.

We demonstrate that the conformation, packing mode, and blue fluorescence of a soft piezofluorochromic compound can be preserved by structurally fixing it into a solid calcium metal–organic framework (Ca-MOF, LIFM-40), which can survive pressures up to 8 MPa. DFT calculations have been combined with experimental results to indicate that the ligands adopting a specific conformation and packing without π···π interactions are the reasons for its rigidified blue emission.

A sacrificial template strategy is developed for the synthesis of yolk-shell Au@ZIF-8 nanoreactor. The Au@ZIF-8 nanoreactor possesses single-crystalline metal-organic framework (MOF) shell with intrinsic monodisperse micropores and introduced macropores. In each of the macropores, one Au NP is encapsulated to form a nanoreactor unit. The quantity of the reactor units in the MOF shell can be readily regulated. Such structure features of the Au@ZIF-8 nanoreactor facilitate the size selectivity of reactants, the accessibility of Au nanoparticles to reactants, and the mass transfer of reactants and products. As a result, the Au@ZIF-8 nanoreactor delivers excellent size selectivity, enhanced conversion, and good cycling stability when used to catalyze the aerobic oxidation of alcohols with different molecular size.

We report herein an unprecedented example of a luminescent Sm(III) metal-organic framework (Sm-MOF), in which both the visible and near-infrared (NIR) emissions of Sm(3+) ions are able to be sensitized by an excited-state intramolecular proton transfer (ESIPT) ligand. Due to the solvent-mediated interchange between enol and keto excited states of the ligand and subsequent energy transfer rate to Sm(3+) ions, the luminescent decay lifetime of the Sm-MOF can be tuned in different solvent-grinding systems.

A novel magnetic coupling is observed in a unpublished crystal that consists of a mono-nuclear manganese(II) complex, namely, [Mn(DPP)(NCS) 2 ] (DPP = 2-(3,5-dimethyl-1H-pyrazol-1-yl)-1,10-phenanthroline), in which neutral DPP molecule functions as tridentate chelated ligand. In the complex Mn(II) ion assumes a distorted trigonal bipyramidal geometry and in the crystal there is a π–π stacking interaction between the adjacent complexes, which involves pyridyl ring and the symmetry-related pyrazolyl ring and pyridyl ring. The fitting for the data of the variable-temperature magnetic susceptibilities with infinite uniform Mn(II) chain formula gave the magnetic coupling constant J = −0.11 cm −1 , and theoretical calculations reveal that there exists a very weak anti-ferromagnetic coupling between the adjacent Mn(II) ions with J = −0.02 cm −1 . The magnetic coupling sign is explained based on McConnell I spin-polarization mechanism with the analysis of the spin density population and the factors that dominate the magnetic coupling magnitude.

The capacity of anode materials plays a critical role in the performance of lithium-ion batteries. Using the nanocrystals of oxygen-free metal-organic framework ZIF-67 as precursor, a one-step calcination approach toward the controlled synthesis of CoO nanoparticle cookies with excellent anodic performances is developed in this work. The CoO nanoparticle cookies feature highly porous structure composed of small CoO nanoparticles (≈12 nm in diameter) and nitrogen-rich graphitic carbon matrix (≈18 at% in nitrogen content). Benefiting from such unique structure, the CoO nanoparticle cookies are capable of delivering superior specific capacity and cycling stability (1383 mA h g(-1) after 200 runs at 100 mA g(-1) ) over those of CoO and graphite.

A new type of ILCT ligand was designed to sensitize both visible and NIR emission of a Pr3+complex, and tunable single component white light and a dual-channel barcode module was achieved in Pr(iii)-MOFs for the first time.

According to land spatial data sharing demands, study the re lation for special data transmission velocity on-line and data quantity by experiments in this contribution. It has educed some valuable conclusions through analysed the result of experimentation of the on-line land spatial data piecemeal transmission experiment. When transmission’s block data size of the land spatial data is in the 1MB scope, the each ti me transmission’s speed time is the shortest when the block data size is 8KB.Certainly,the transmission’s speed time is Not too discrepancy when each time the transmission’s block data size is between 4KB and 32KB. When transmits the land spatial data size between 1MB and 200MB, the block data size which waste the least transmission time is 32KB. When transmits the land spatial data size around 350MB, the block data size which waste the least transmission time is 512KB. Key words: land; spaical data; transmission ÷ spatial data sharing 1. INTRODUCTION With the popularization of information technique, land information sharing has been became inevitable trend.The key of land information sharing is land spatial data sharing.Besides the form of data transmission,transmission speed on line is also one of factor which influence land spatial data sharing to land spatial data sharing on line. Spatial data transmission on line is always the pivotal technology in GIS data sharing.In recent years,many scholars are working on research in this area, although many scholars study a good platform for the sharing system[2][3][4],even some countries have also introduced a spatial data exchange standards[1], but few su itable for network transmission characteristics of the spatial data transmission of data research results. Effort of spatial data sharing is related to transmission speed on line, and transmission speed is not only related to bandwidth, but also related to data quantity of every transmission. It is known to all of us that different form of da ta storage has different data quantity. Howe ver,there has not been complete,systemic research effort which is concerned that how different between every transmission data quantity and total time of transmission. Although the fifth literature studied the best transmission data quantity on line of grid data, it has not embedded in vector data or data transmission which is stored in file formats. Therefore,through analysed the result of experimentation this text will do systematic research in the best transmission quantity of spatial data on line,and then find relations between data quantity and spatial data tr ansmission which is suitable for network environment.